Question

我正在使用https://github.com/log0/video_streaming_with_flask_example中的代码来传输来自相机的视频并将其公开。我可以用这段代码完成它，但我需要在外部应用程序中用OpenCV分析视频，所以我需要在那个python脚本中加载它。

我使用此代码

camera.py

import cv2

class VideoCamera(object):
    def __init__(self):
        # Using OpenCV to capture from device 0. If you have trouble capturing
        # from a webcam, comment the line below out and use a video file
        # instead.
        self.video = cv2.VideoCapture(0)
        # If you decide to use video.mp4, you must have this file in the folder
        # as the main.py.
        # self.video = cv2.VideoCapture('video.mp4')

    def __del__(self):
        self.video.release()

    def get_frame(self):
        success, image = self.video.read()
        # We are using Motion JPEG, but OpenCV defaults to capture raw images,
        # so we must encode it into JPEG in order to correctly display the
        # video stream.
        ret, jpeg = cv2.imencode('.jpg', image)
        return jpeg.tobytes()

和main.py

from flask import Flask, render_template, Response
from camera import VideoCamera

app = Flask(__name__)

@app.route('/')
def index():
    return render_template('index.html')

def gen(camera):
    while True:
        frame = camera.get_frame()
        yield (b'--frame\r\n'
               b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n\r\n')

@app.route('/video_feed')
def video_feed():
    return Response(gen(VideoCamera()),
                    mimetype='multipart/x-mixed-replace; boundary=frame')

if __name__ == '__main__':
    app.run(host='127.0.0.1', debug=True)

当我运行这两个脚本时，我得到页面127.0.0.1:5000，我可以看到视频。我需要做的是像这样流式传输视频，但是要在一些使用OpenCV进行某些分析的外部python脚本中导入它

cap = cv2.VideoCapture('127.0.0.1:5000')

但它不起作用，我收到错误

warning: Error opening file (/build/opencv/modules/videoio/src/cap_ffmpeg_impl.hpp:808)
warning: 127.0.0.1:5000 (/build/opencv/modules/videoio/src/cap_ffmpeg_impl.hpp:809)
OpenCV Error: Assertion failed (size.width>0 && size.height>0) in cv::imshow, file C:\projects\opencv-python\opencv\modules\highgui\src\window.cpp, line 331
Traceback (most recent call last):

我知道localhost在外面是看不到的，但是我会在解决这个问题后立即将它放在公共IP上，以便在不导入VideoCamera类的情况下使其工作。如果它现在可以在我的电脑上运行就足够了。

我如何在一个脚本中使用python传输视频，然后加载它并在另一个脚本中使用OpenCV进行分析？

0 个答案: